Mastering Python: A Beginner’s Guide to Writing Comments

Introduction to Writing Comments in Python

Programming in any language is not just about writing code that a computer can understand. It’s equally important to write code that fellow programmers and even your future self can understand. This is where the power of comments in Python comes into play. As a beginner, mastering the art of commenting is crucial to developing clean, maintainable, and collaborative code. In this guide, we will explore why comments are important, the types of comments in Python, and best practices for writing effective comments.

The Importance of Comments in Python

Comments are lines in your code that are ignored by the interpreter. Their main purpose is for the reader of the code, making your programs much easier to understand. They can explain what a section of code does, why it’s there, and any other contextual information. This is especially useful in complex or lengthy programs where the purpose of a section of code might not be immediately evident.

Types of Comments in Python

  • Single-Line Comments: As the name suggests, these comments span only a single line and are created by prefixing the line with a hash symbol (#).
  • Multi-Line Comments: Python doesn’t technically have a specific syntax for multi-line comments. However, you can use triple quotes (either ”’ or ) to create a string that spans multiple lines, which the Python interpreter will ignore if not assigned to a variable.
  • Docstrings: Short for documentation strings, docstrings are string literals that appear right after the definition of a function, method, class, or module. They are denoted by triple quotes and can span multiple lines. Docstrings are used to generate automatic documentation.

Best Practices for Writing Comments

While commenting is crucial, overcommenting or writing unclear comments can be counterproductive. Here are some guidelines to help you write useful comments:

  • Stay Relevant: Your comments should provide additional insight that isn’t immediately obvious from the code.
  • Keep It Simple: Comments should be concise and easy to understand.
  • Update Regularly: Make sure to update comments if you change your code, as outdated comments can be misleading.
  • Use Docstrings: For functions, methods, classes, and modules, use docstrings to explain their purpose and usage.
  • Avoid Commenting Out Code: Instead of leaving chunks of unused code in comments, remove them. Version control is a better tool for preserving old versions of your code.

Examples of Comments

To help illustrate, let’s look at some examples:

# This is a single-line comment
print(Hello, world!)  # Inline comment

This is a multi-line comment.
It can span several lines.

def my_function():
    This function prints Hello, World!
    print(Hello, World!)

External Resources for Further Reading

To gain a deeper understanding of writing comments and other Python best practices, the following resources are invaluable:

  • PEP 8 — Style Guide for Python Code: This guide provides conventions for writing readable code, including how to effectively use comments.
  • The Python Tutorial: The official Python documentation offers a comprehensive guide to all aspects of Python programming.
  • Real Python: Offers tutorials and articles on a wide range of Python topics, including comments and docstrings.
  • Learn Python: A beginner-friendly platform that offers interactive Python tutorials.

Conclusion: Putting It All Together

Mastering the art of writing comments in Python is a fundamental step towards becoming an efficient programmer. It not only aids in code understanding and maintenance but also facilitates better collaboration among team members. By adhering to the best practices outlined in this guide, beginners can write more readable and maintainable code.

Depending on the use case, different approaches to commenting may be more appropriate:

  • For solo projects: Focus on docstrings for public functions and classes to make sure that your code is understandable when you come back to it later.
  • For team projects: Prioritize clear, concise comments that explain complex logic or decisions that cannot be understood from the code alone.
  • For open-source projects: Comprehensive comments including docstrings, module, and function explanations are crucial for enabling others to contribute effectively.


What is the purpose of comments in Python?

Comments are used to explain code and make it more understandable for humans. They can describe the purpose of a section of code, provide context, or explain complex logic.

When should I use multi-line comments instead of single-line comments?

Use multi-line comments when you need to write an explanation that spans several lines, such as a detailed description of a function or module. For short comments, single-line comments are preferred.

Are comments considered good practice in programming?

Yes, comments are considered good practice when used appropriately. They enhance the readability and maintainability of code. However, overcommenting or outdated comments can be detrimental.

How do I write effective docstrings in Python?

Effective docstrings should describe the purpose of a function, method, class, or module, list its arguments and return values, and include examples of how to use it if necessary.

Can commenting out code be useful?

Commenting out code can be useful temporarily for debugging purposes, but it’s generally not recommended to leave large blocks of commented-out code in your project. Version control systems are a better way to manage old or alternative versions of code.

Learning to write effective comments is a valuable skill that will serve you throughout your coding journey. Remember, the goal of comments is not just to explain what your code does, but also why it does it. As you grow as a programmer, your ability to communicate through comments will greatly enhance the clarity and usefulness of your code. If you have any questions, corrections, or experiences you’d like to share about commenting in Python, feel free to contribute to the discussion below.